The undeniably well-proportioned 2009 Audi S5 marks a late but bold entrance into the luxury performance coupe segment for Audi. A high-performance version of the company's sleek A5, the S5 was actually launched before the "garden-variety" A5, which speaks volumes about Audi's commitment to its performance image. As M is to BMW and AMG to Mercedes, Audi's "S" cars are high performance versions of existing models. While the S5 is no exception to the rule, it is our experience is that it is not as uncompromisingly geared toward performance as BMW's M3, or as luxury oriented as the Mercedes-Benz CLK 550.